A refereeing colleague said to me recently, ‘what are these extra officials who stand on the goal line supposed to do? He had been watching Champions League matches and was referring to the two Additional Assistant Referees as they are officially titled. He ought to have known, because their duties appear in the Laws of the Game, having been approved in 2013 as an option that competitions can take.
They are the brainchild of Marcel Platini as President of UEFA; his answer to Goal Line Technology which he rejects. It is not surprising therefore, that their first duty is to indicate to the referee, when the ball wholly crosses the goal line, especially of course between the goal post and under the cross bar. This has not been wholly successful, remember the England/Ukraine game in the last European Championships and there have been other errors.
So more duties were added, some of which usurp those of the assistant referees. They indicate whether it is a goal kick or corner, when misconduct or any other incident occurs out of the view of the referee, when offences are committed whenever they have a better view than the referee, particularly in the penalty area and whether the goalkeeper moves off his line at a penalty. Their indications are of course not by flag but by radio communication, via their mini-microphones.
These additional assistant referees must be of the highest standard available, therefore you will see some of our top referees in their tights and gloves lingering on goal lines. But do they work? I remember Howard Webb when he was still refereeing, praise them and say they cut down the holding and pushing in the penalty area. Assistant referees claim they help them too, because they can concentrate solely on offsides.
These highly qualified and experienced additional assistant referees only give indications of course, for as the laws say, the final decision always lies with the referee.